Indicate whether the following statements are always true or can befalse. (Selec

Question

Indicate whether the following statements are always true or can befalse.
(Select T-True, F-False. If the first is F and the rest T,enter
FTTTTT).

A) An object's velocity will change if a net force acts on theobject.
B) If a net force acts on an object, the object's speed willchange.
C) In order not to slow down, a car moving at a constant velocityneeds a small net force applied.
D) If two objects have the same acceleration, they are under theinfluence of equal forces.
E) During the collision of a car with a large truck, the truckexerts a greater force on the car than the car exerts on thetruck.
F) The net force which acts on an object which remains at rest iszero.

I have tried several combinations, and am pretty sure that A=T,E=F, and F=T, but am unsure about the other. Please help!

Explanation / Answer

T , F , F*, F, F, T That is becoz : (B) Take the example of magnetic force on a movingcharged body in a uniform magnetic field perpendicular to itsvelocity at all time.    Speed will change if there is a change in kineticenergy, ie. some work is done.    So, if force and velocity areperpendicular,    F.v = Fvcos90 = power = 0    So, work done = 0. (C) If you consider ideal situation(no slipping orfriction in other parts of car)        according tonewton's first law no force is required however in realsituation it is required.          So, try F andthen T. (D) if masses are different,               F = ma & F' = m'a are not equal

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